1. Field of the Invention
The present invention relates to a machine for the production/processing of a material web, in particular a fibrous web, for example of paper or board, which comprises at least one treatment section in which the material web can have a treatment fluid applied to it, the treatment section being connected or able to be connected to a treatment fluid source via at least one line connection.
2. Discussion of Background Invention
Machines of this type are known, for example from the papermaking industry. Normally, such machines comprise a plurality of treatment sections in which a treatment liquid is added to the material web. For instance, for the purpose of moisture profiling of a paper web in a drying section or before a calender of a paper machine, use is made of nozzle moisteners which discharge water intermittently onto the paper web. For this purpose, the nozzle moisteners are connected via a line connection to a water supply and valves that can be driven in a pulsating manner are arranged in the nozzle moisteners.
As a result of the pulsating operation of the valves and the associated intermittent transport of the treatment liquid from the water supply through the line connection to the nozzle moisteners, these components of the treatment section are continuously subjected to fast pressure fluctuations, which contribute to high loading and therefore to rapid wear of these components.
Pressure fluctuations can additionally be transmitted to the treatment fluid, for example by a pump connected to the treatment fluid source or by other sources of oscillation connected to the line system.
Generally known for pulsating liquids is an oscillation damper, which comprises a hollow chamber defined in a housing and subdivided by a movable diaphragm into a liquid chamber and a gas chamber. The pressure fluctuations of the pulsating liquid are balanced out or damped as a result of the fact that the diaphragm can give way to a temporary pressure rise by means of intensified compression of the gas volume and, in the case of a temporary pressure drop, permits appropriate expansion of the gas volume. However, such oscillation dampers have the disadvantage that the edge of the diaphragm must be fixed to the housing in a liquid-tight and simultaneously stable manner and, particularly in this edge region, the diaphragm itself is subjected to intense continuous loading. Furthermore, the gas chamber must be sealed off adequately from the outside and it is necessary for means to be provided for filling the gas chamber and for setting the gas pressure, so that the known oscillation damper is overall of relatively complicated construction.